The invention relates to a method for controlling the combustion of a self ignition internal combustion engine, wherein a first fuel amount is first injected in the combustion chamber and a second amount is then injected for combustion with the mixtures.
In the operation of internal combustion engines with direct fuel injection, attempts are made to influence the combustion and the formation of emissions by varying the injection profile. In particular in direct injection internal combustion engines with self ignition, injection strategies are proposed for optimizing the combustion. These strategies are intended to increase the power while simultaneously reducing the exhaust gas emissions. In this context, a significant increase in power is generally made more difficult by excessive formation of soot particles, in particular in the full load engine operating mode.
DE 19953932 A1 discloses a method with which a combined homogenous/heterogeneous operating mode of an internal combustion engine for achieving medium and relatively high power levels is proposed. In said operating mode, both an early homogenous mixture formation in the compression stroke and a subsequent heterogeneous mixture formation around the top dead center position of the piston are to be made possible with an injection strategy. In this context, the fuel injection takes place during the homogenous mixture formation with a lower injection pressure than during the heterogeneous mixture formation in order to avoid fuel being applied to the cold walls of the combustion chamber. Nevertheless it has become apparent that despite the measures proposed above, the exhaust gas emissions continue to be quite high, in particular in the full load operating mode. For this reason, it is necessary to take further measures with which the exhaust gas emissions are minimized.
It is the principal object of the present invention to provide an internal combustion engine with self ignition with which the load is increased while the exhaust gas emissions are simultaneously reduced.